MILWAUKEE SHOCKWAVE IMPACT DUTY SOCKET ADAPTERS ARE ENGINEERED FOR EXTREME DURABILITY AND UP TO 10X LIFE. SHOCKWAVE IMPACT DUTY SOCKET ADAPTERS ARE MADE FROM PROPRIETARY STEEL AND HEAT TREATED TO CONTROL HARDNESS. FEATURES UL STYLE""MARGIN-TOP0PX;PADDING-TOP 5PX; PADDING-BOTTOM 5PX;"" PROPRIETARY STEEL AND HEAT TREAT PROCESS FOR MAXIMUM STRENGTH AND DURABILITY